During the Buddha mission of the anime (in the English version only), Konta makes a reference to the movie Shaft in which Tomao tells him to "Shut your mouth" to which Konta replied with "But you can dig it can't you" which is a reference to the popularized theme song.
In the anime, the notebook computer that Nishi used to keep track of the 'games' was an Apple PowerBook G4.
The stronger 'Vampires' in the Gantz universe are dressed in formal suits and wear sunglasses. They bear a strong presence and resemblance to the 'Agents' from 'The Matrix' trilogy. Both parties are similar in that they wear similar attire, and are both considered 'unbeatable'.
Volume 3, Issue 29: Tetsuo Nemoto is the leader of the Bosozoku Japanese motorcycle gang that partakes in the Tanaka Alien Mission.
Volume 4, Issue 37: The Tanaka Alien's words "Hey, hey, hey, it's a beautiful day" are Daniel Boone's "Beautiful Day." This was covered in 1976 by Japanese singer Seiji Tanaka. The Tanaka Alien (Tanaka Seijin) is a play on his name in Japanese (Tanaka Seiji). The other things the Alien say are bits of his other songs and "Yuzo" is the name of his cousin. His name was changed in the anime to "Suzuki Alien" perhaps due to Seiji's discontent of his portrayal.
Volume 4, Issue 40: Yoshinoya (吉野家) is the largest chain among beef bowl (Gyūdon) restaurants and one of the leading fast food chains in Japan; often shortened to "Yoshigyū" (meaning Yoshinoya's beef) among its enthusiasts.
Volume 5, Issue 47: (1) "Yuzo" refers to Yuzo Gucci, the original singer on the show "Together With Mom," a cousin of Seiji Tanaka who was the lead singer of the comedic band "Busy Four" and famous for his impersonations of Tanaka. The "Haah" and "beautiful" lines originate from the lyrics of his biggest hit, "Beautiful Sunday." Famous Watermelon Lands and "Did you make some friends" are lines from his "Famous Watermelon Lands" song. (2) Kagoshima Prefecture is where his current record label is located at. (3) His sidekick "Gyoro-chan" is a grotesque take-off of a "Choco Ball" Morinaga Confections mascot, "Kyoro-chan." Tanaka was well-known for his appearance in Morinaga commercials from 1973 to 1988.
Volume 5, Issue 56: Oolong tea is a traditional Chinese type of tea.
Volume 5, Issue 57: (1) Sei Sakuraoka from the Buddha Mission looks like Lara Croft from Tomb Raider. (2) Musou Tokugawa, the monk from the Buddha Mission, looks like the Japanese television personality Odamudo. (3) Tougou Juuzou (the sniper in the military fatigues in the Buddha Mission) looks like Duke Togo, the codename for the assassin from Golgo 13. (4) JJ, the American karate practitioner from the Buddha Mission, looks like Geese Howard from SNK. (5) Tomao from the Buddha Mission looks like the Japanese actor Yosuke Kubozuka. (6) Tomao's friend, Konta, also from the Buddha Mission looks like Kawabata Kaname, a Japanese musician from Chemistry. (7) "Namuami Dabutsu" is a Japanese Buddhist prayer meaning "I take refuge in Amida Buddha."
Volume 6, Issue 67: The Buddhist Temple Alien statue that appears on the rooftop looks like one of the Buddhist Bishamonten or Tamonten deities who are in statue form in Kamakura.
Volume 6, Issue 68: Among the remaining Buddhist Temple Aliens are the Tentouki (Tentoki) and Ryuutoki (Ryutoki) creature who hold lantern. Though originally evil, they were trampled by the Shitenno (Four Deva Kings), repented, were saved, and now carry lanterns as offerings for the Buddha.
Volume 6, Issue 69: The big Buddhist Temple Alien is based on a Buddha statue located at Tōdai-ji Temple in Nara. In the anime version, JJ even comments: "Wow, cool! It's a Japanese Daibutsu!"
Volume 17, Issue 191: Oni Mission takes place in Ikebukuro.
Issue 228: One of the girls hitting on Akira Kurono and his friends looks like Chiaki Kuriyama.
Issue 232: Izumi Shion fights the Vampires in Chiyoda Park outside of Mizuo Train Station.
Issue 233: Razor Ramon HG is shown on Kei Kurono's television while flipping through channels.
Issue 234: Kei Kurono goes to shop in Akihabara to find a counter weapon against the Vampires.
Issue 235: The subtext of: "The dew may stay on the withered flower, but it will never see another evening." of the issue's title is borrowed from Hōjōki (1212) by Japanese authorKamo no Chōmei (1155-1216).